<?php
if (!isset ($_SESSION)) {
	ob_start();
	session_start();
}
 $con=mysqli_connect("127.0.0.1","BookSharing","BookSharing","BookSharing"); 
 if (mysqli_connect_errno($con)){ 
	 echo "连接 MySQL 失败: " . mysqli_connect_error(); 
 }
 mysqli_query($con,"set names utf8");
 
 